The present invention relates to a pneumatic tire, more particularly to a rain tire suitable for running on wet roads at high speed in motor sports.
There has been known a pneumatic tire provided in its tread portion with main grooves with a large width and depth (i.e. a large groove volume) for the purpose of improving the drainage performance on wet roads. However, in the tread portion, if the groove volume is increased, the ground contacting area is decreased and the rigidity of the tread portion in its land regions is lowered, therefore, there has been a problem that the steering stability on dry roads is deteriorated. Especially in motor sports, it is important for a rain tire, which is intended for running on a wet road surface at high speed, to improve the steering stability to a higher level while maintaining the wet performance.